mberns@ut-ngp.UUCP (Mark Bernstein) (11/13/85)
[] How can one tell if front MacPherson strut cartridges are significantly worn out and in need of replacement? I know it's obvious if they are leaking, or if the car rebounds wildly if you push down on a corner of the car (the "classic" test :-) ). But how about more subtle wearing out due to age, if there is such a phenomenon? My car is a 1980 Volvo, ~54,000 miles. A mechanic doing some other work pointed out that he thought the struts were showing "signs of wear" - noting some shiny bare metal streaks on the housing under the rubber dust boot just above the main spring - he said that indicated excessive travel & bottoming out. He also pointed out some *very* subtle staining in the dirt which encrusts the whole assembly, saying that was an indication of a little leaking, from age. I wouldn't have noticed the "stain" as an obvious leakage. He claims that after 5 years and 54K miles, struts would be on their last legs if not gone, and should be replaced. For $275 or so for gas pressurized struts and rear shocks, installed. Of course. My regular mechanic says that he has seen them last for 80 - 100K miles, and as long as you bounce the corner of the car and it still feels stiff and doesn't rebound beyond one bounce, you're ok. Naturally, if I try this they seem fine. Which is why I'm asking about all this. Is there any way of knowing who's "right", short of simply replacing the struts? Obviously I'd just as soon not spend that money, but on the other hand, it makes me crazy to drive a car which is not performing as it should I will admit that I don't notice any particular handling or ride difficulties, BUT: I've been driving the car daily for 5 years, and a *gradual* deterioration of handling and stability - not to dangerous levels - might not be noticeable to me, in the sense that a set of new shocks might be a pleasant surprise, bringing the car back to its original handling, which I may have "forgotten". And, the "push down on the fender and see what happens" test seems awfully simpleminded and unsubtle, given the generally taut springing and stabilizer bars found on European cars of this type. That test might do fine for a softly sprung full size Chevvie, but is it truly appropriate for this car? Any ideas would be greatly appreciated. -Mark Bernstein (UT Austin, Speech)
pwv@fluke.UUCP (Pat Vilbrandt) (11/18/85)
> How can one tell if front MacPherson strut cartridges are significantly > worn out and in need of replacement? ... > -Mark Bernstein (UT Austin, Speech) My experience ranges from struts that were totally, obviously shot after 50K miles (Mercury Capri) to struts that gave only a slightly harsher ride at 105K mi. (Subaru). The function of "dampers" (shocks, struts, et. al.) is to "damp out" the natural resonance of an automobiles suspension. Thus they really only come into play when driving over an irregular surface. They have little to do with cornering ability, nose dives during stops, etc. The way I determine the relative health of struts: - Examine the struts for *obvious* signs of leaking, wear, damage. - When doing the classic "bounce test", do the struts make noises (creeks and groans) or stick (esp. after the car sits undisturbed for awhile)? - Does the front end make noises when doing tight maneuvering at slow speeds? - Is the handling overly harsh or unstable when driving over bumps or holes at moderate (~45 mph) speeds? If the above uncovers nothing out of ordinary, your struts are probably still relatively healthy. True, as with any moving part, the performance of struts will gradually decline with age as they wear. If you are driving a "performance" car and you tend to drive hard, 50K miles is a reasonable strut replacement interval. If you are a more sedate driver of a not-so performance vehicle, you probably don't need to replace your struts as often. Beware of garages/dealers/mechanics that say: "yer ______ needs replacing" and can not give you hard evidence of the fact. They are out to get your business ($$). It's easy to argue that shocks/struts begin to wear immediately from use and should regularly be replaced, but if your car rides and handles fine, you will probably see very little improvement from replacing them. Good Luck! -- Pat Vilbrandt John Fluke Mfg. Co., Inc. Everett, Washington USA UUCP: { decvax!uw-beaver, ucbvax!lbl-csam, allegra, ssc-vax, decwrl!sun }!fluke!pwv ARPA: fluke!pwv@uw-beaver.ARPA
quint@caip.RUTGERS.EDU (Amqueue) (11/22/85)
> How can one tell if front MacPherson strut cartridges are significantly > worn out and in need of replacement? ... > -Mark Bernstein (UT Austin, Speech) I have two roommates with MacP struts in their cars. One is a Rabbit and one is a Dodge Omni, rabbit clone style. The Rabbit owner was wondering the same thing, as she has had the car for 80,000 (or close) miles and the car wasnt wallowing or having any of the other classic signs of shock/ strut wear. She had them checked because she was having a shimmy problem in the front end, and it turned out that there are 2 ways the struts can go bad: one by getting progressively mushier and softer, which is the classic way that everyone knows, and one by getting progressively *harder*. The Rabbit had always had a rougher ride than other cars, so she didnt really notice the increase in jolt and noise, especially noticeable when going over a set of railroad tracks near the house. she had them replaced, and she no longer has a "front end problem", and the car has gotten much quieter and nicer especially over those tracks. Tho Omni, on the other hand, is starting to feel like a car 3 times its size. It has a nice harmonic bounce with the sectioning of the local roads, and is probably going to get them changed soon. Unfortunately, we cant be sure how many miles this car has, nor how many times the struts have been changed, since we bought it used. The mileage is most likely 125K+. hope this provides some useful info /amqueue